SECONDARY BATTERY

An embodiment of the present invention relates to a secondary battery, and with respect to a technical problem to be resolved, provided is a secondary battery which has an electrode tab provided by forming a notch on a non-coated part of an electrode plate of an electrode assembly, and which can enable a current collecting plate to come into surface contact with the electrode tab. To this end, disclosed is a secondary battery comprising: an electrode assembly which comprises a first electrode plate coated with a first electrode active material and having a first non-coated part formed along an upper end thereof, a second electrode plate coated with a second electrode active material and having a second non-coated part formed along a lower end thereof, and a separator interposed between the first electrode plate and the second electrode plate, and which is wound in a jelly roll shape; a can for accommodating the electrode assembly; a cap assembly for sealing the can; a first current collecting plate electrically connected to the cap assembly by coming into contact with the first non-coated part; and a second current collecting plate electrically connected to the can by coming into contact with the second non-coated part, wherein the first non-coated part and/or the second non-coated part has a structure in which a plurality of isosceles trapezoidal electrode tabs are arranged to be adjacent to one another with notches formed at a specific angle (α) and at predetermined intervals from a start point thereof that is closest to a winding axis, and thus the first non-coated part and/or the second non-coated part are bent toward the winding axis.